Reduced patellofemoral and walking pain with mobile-bearing vs. fixed-bearing total knee replacements: a mid-term prospective analytic study.

Abstract

Total knee replacement (TKR) is the standard treatment for advanced stage knee osteoarthritis. The introduction of the mobile-bearing (MB) design has given rise to a series of theoretical advantages compared to fixed-bearing (FB) implants, although current literature does not reveal significant differences between the designs. The aim of this study was to estimate the clinical results of 2 cemented total knee prosthetic designs: an MB and an FB design. A series of patients with similar clinical and radiographic characteristics were treated consecutively with 100 FB followed by 94 MB implants. Patients were evaluated radiographically and clinically. Statistically significant differences were found in terms of pain at 5 years in favor of MB prostheses (p=0.006). The "pain on ascending/descending stairs" category on the KSS score showed improvement at 5 years for the MB design (p=0.003). MB implants showed better results in terms of ability to ascend/descend stairs at five years (p=0.002). With regards to the patients' ability to walk, there were differences at 1 year (p=0.020) and at 5 years (p=0.021) in favor of MB implants. At a mean follow-up of 5 years, significant differences were observed in the MB prosthesis in terms of postoperative pain, ability to ascend/descend stairs, and patellofemoral pain.